CN111884915A

CN111884915A - Method for improving efficiency of acquiring modbus equipment by gateway

Info

Publication number: CN111884915A
Application number: CN202010690219.4A
Authority: CN
Inventors: 陈科明; 吴新虎; 吴耀增; 曾佳
Original assignee: Hangzhou Dianzi University
Current assignee: Hangzhou Dianzi University
Priority date: 2020-07-17
Filing date: 2020-07-17
Publication date: 2020-11-03

Abstract

The invention discloses a method for improving efficiency of acquiring modbus equipment by a gateway. The invention improves the information acquisition efficiency by sequencing and resetting the continuous units. The modbus device in the invention has stack number, register address and data type. The gateway stores information for the corresponding modbus device, setting each register address and data unit as a monitoring point. The monitoring points are sorted from small to large according to the addresses of the registers. The read address and the length of the read data are reset at address intervals. The gateway establishes a corresponding modbus frame to be issued, the equipment replies, data are matched into a corresponding monitoring point, and then data information of the monitoring point is reported to the cloud platform.

Description

Method for improving efficiency of acquiring modbus equipment by gateway

Technical Field

The invention relates to the technical field of communication of the Internet of things, in particular to a method for acquiring information of equipment and improving information acquisition efficiency through a modbus protocol based on a gateway of a 4G, WiFi and Ethernet networking mode.

Background

Modbus was developed by MODICON in 1979 and is an industry field bus protocol standard. The company Schneider introduced the Modbus protocol based on Ethernet TCP/IP in 1996: ModbusTCP. The Modbus protocol is an application layer message transmission protocol and comprises three message types of ASCII, RTU and TCP. The standard Modbus protocol physical layer interface comprises RS232, RS422, RS485 and an Ethernet interface, and adopts a master/slave mode for communication. When the traditional gateway reads data by adopting a modbus protocol, polling of the data is carried out on each monitoring point. All need establish corresponding modbus frame and issue to corresponding equipment, add serial ports communication rate limited, and adopt the realization mode of a reply in the modbus agreement, there is the latency of answering in the middle of, when there are a plurality of discontinuous monitoring points, a monitoring point goes the polling, the inefficiency of reading. When the polling is too slow, the real-time information reported by the gateway also becomes slow, so that an error occurs between the information on the cloud platform and the actual information of the equipment, and a part of information is lost.

Disclosure of Invention

The technical problem to be solved by the present invention is to provide a method for acquiring gateway data to solve the problems and deficiencies in the background art.

The technical problem solved by the invention is realized by adopting the following technical scheme:

a method for improving efficiency of collecting modbus devices by a gateway comprises the following steps:

step 1, the gateway and the equipment are correspondingly connected, and the gateway is connected to the cloud platform.

And 2, acquiring the stack number and the register address of the device to be read by the gateway. And determining the type of data needing to be read in each address, and recording the address information and the type of the read data in the monitoring point.

And 3, arranging the information of the monitoring points from small to large according to the sequence of the addresses, and storing the information in a linked list mode. And detecting whether the arranged monitoring points are continuous or not, wherein the continuous definition is that the address difference is less than 3, and the judgment of continuity can be carried out. The difference of the addresses can be regulated.

And 4, determining a starting monitoring point and an ending monitoring point. The initial monitoring point is the first monitoring point after the discontinuity; the termination monitoring point is the last consecutive monitoring point. And acquiring the length and the type of data to be read from the starting monitoring point to the ending monitoring point.

And 5, establishing a relevant modbus frame by starting the address in the monitoring node and the data length and the data type acquired in the step 4, and issuing the modbus frame to the corresponding node.

And 6, matching the information returned by the node according to the information from the starting monitoring point to the ending monitoring point, and reporting the matched data to the cloud platform.

Compared with the prior art, the invention has the beneficial effects that: through the adjustment of the monitoring points, continuous reading operation is performed, the reading times and the corresponding waiting time are reduced, and the efficiency of acquiring node information by the gateway is improved.

Drawings

FIG. 1: a system structure diagram;

FIG. 2: a single monitoring point illustration;

FIG. 3: sequencing a read-through explanatory diagram by the monitoring points;

FIG. 4: modbus frame format diagram.

Detailed Description

The following detailed description of the preferred embodiments of the present invention, taken in conjunction with the accompanying drawings, will make the advantages and features of the invention more readily understandable by those skilled in the art, and thus will more clearly define the scope of the invention.

The invention utilizes the modbus continuous reading function to change the reading of single data into the continuous rule for finding the data, sets different intervals and reads the data in the corresponding address. Matching the data and reporting to the cloud platform

The implementation of the invention comprises the following steps:

referring to fig. 1, in step 1, the gateway has a networking mode of 4G, WIFI and ethernet, connects to a corresponding cloud platform, and reports the collected information of the device to the cloud platform. And the gateway serial port is connected with the serial port of the equipment, and the adopted communication mode is a modbus communication protocol to obtain the stack number of the equipment.

Referring to fig. 2 and fig. 3, step 2, building corresponding monitoring points, where one monitoring point stores the address of the register, the information of the data type, and the information of the reported data unit. The address and data type of the register identify what the gateway needs to read. And reporting the data unit information, storing the data returned by the equipment, and reporting the data to the cloud platform by the gateway. And adding a plurality of monitoring points into the gateway, and storing the information of the monitoring points by the gateway.

And 3, sequencing the corresponding monitoring points from small to large according to the addresses, and setting a continuous data interval as 3. It is first necessary to determine the starting monitoring point and then the ending monitoring point. 4001 no other monitoring points before the monitoring point are determined as the starting monitoring point, 4002 is less than 4001 and is determined as continuous, 4005 is less than 4002 and is equal to 3 and is determined as continuous, 4006 is less than 4005 and is less than 3 and is determined as continuous, 4008 is less than 4006 and is determined as continuous, 4012 is greater than 4008 and is determined as discontinuous, and 4008 is set as the ending monitoring point. The following monitoring points repeat the above method to find the next starting monitoring point and the next ending monitoring point.

And 4, polling data, and determining a modbus frame format through the data from the starting monitoring point to the ending monitoring point. And acquiring a starting address from the starting monitoring point, and then accumulating the data types of each monitoring point from the starting monitoring point to the ending monitoring point to acquire the length of the data to be read.

Referring to fig. 4, in step 5, a corresponding modbus frame is established, the corresponding frame format is adopted, the device address is a stack number, the function code is a read function code 0x03, the start address and the data length are the data acquired in step 4, the data are sent through the serial port, and the device waits for a reply.

And 6, matching the returned information with the monitoring points, intercepting corresponding data according to the data type of each monitoring point of the read information, and filling the corresponding monitoring point data unit with the intercepted corresponding data.

And the gateway reports the data unit of each monitoring point to the cloud platform.

The above description is only an embodiment of the present invention, and not intended to limit the scope of the present invention, and all equivalent structures or equivalent flow transformations made by using the contents of the specification and the drawings, or applied directly or indirectly to other related technical fields, are included in the scope of the present invention.

Claims

1. A method for improving efficiency of a gateway in collecting modbus devices is characterized by comprising the following steps:

step 1, a gateway and equipment are correspondingly connected, and the gateway is connected to a cloud platform;

step 2, acquiring the stack number and the register address of the device to be read by the gateway; determining the type of data to be read in each address, and recording the address information and the type of the read data in a monitoring point;

step 3, arranging the information of the monitoring points from small to large according to the sequence of addresses, and storing the information in a linked list mode; detecting the arranged monitoring points to judge whether the monitoring points are continuous or not, and judging that the monitoring points are continuous when the address difference is smaller than a set threshold;

step 4, determining an initial monitoring point and a termination monitoring point; the initial monitoring point is the first monitoring point after the discontinuity, and the termination monitoring point is the last continuous monitoring point; acquiring the length and the type of data to be read from an initial monitoring point to a final monitoring point;

step 5, establishing a relevant modbus frame through the address in the initial monitoring node and the data length and the data type obtained in the step 4, and issuing the modbus frame to the corresponding node;

2. The method of improving efficiency of a gateway collecting modbus devices of claim 1, wherein: the RTU format of the modbus frame comprises a device address bit, a function code bit, a start address bit, a data length bit and a CRC check bit, wherein the function code bit is related to the threshold value.